透析icmp协议(三): 牛刀初试之一
应用篇ping(icmp.dll)
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这篇文章出自:http://tangentsoft.net/wskfaq/examples/dllping.html
翻译: bugfree/csdn, 对原始代码加了些注释
平台: vc6 windows xp
原理简介:
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这个例子演示了应用微软的icmp.dll怎样"ping"另一台机器. 这个dll是没有文档话的发送icmp回送包api接口, 也称为"pings," 就像潜水员对声纳信号的术语一样. 这段代码出自一个被一个名叫markg的家伙的gui程序, 他的网页已经消失了.
icmp.dll api 现在在windows平台上与微软的winsocks工作的很好, 但是微软说更好的产品一出来他们将替换它. 微软说这个自从windows 95时代就在用, 这些功能在在windows 2000上仍然存在.
for more information on the icmp.dll api, check out sockets.com's icmp api page.
更详细的icmp.dll api的信息到sockets.com的icmp api网页获取.
具体实现:
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// borland c++ 5.0: bcc32.cpp ping.cpp
// visual c++ 5.0: cl ping.cpp wsock32.lib
//
// this sample program is hereby placed in the public domain.
#include <iostream.h>
#include <winsock.h>
#include <windowsx.h>
#include "icmpdefs.h"
==================ping的实现部分==================
int doit(int argc, char* argv[])
{//[bugfree] 建议将这个argc和argv的处理拿到main函数中
// 检查命令行参数
if (argc < 2) {
cerr << "usage: ping <host>" << endl;
return 1;
}
// 装载icmp.dll连接库
hinstance hicmp = loadlibrary("icmp.dll");
if (hicmp == 0) {
cerr << "unable to locate icmp.dll!" << endl;
return 2;
}
// 查找给定机器的ip地址信息
struct hostent* phe;
if ((phe = gethostbyname(argv[1])) == 0) {
cerr << "could not find ip address for " << argv[1] << endl;
return 3;
}
// 定义函数三个指针类型
typedef handle (winapi* pfnhv)(void);
typedef bool (winapi* pfnbh)(handle);
typedef dword (winapi* pfndhdpwpippdd)(handle, dword, lpvoid, word,
pip_option_information, lpvoid, dword, dword); // evil, no?
//定义三个指针函数
pfnhv picmpcreatefile;
pfnbh picmpclosehandle;
pfndhdpwpippdd picmpsendecho;
//从icmp.dll中得到函数入口地址
picmpcreatefile = (pfnhv)getprocaddress(hicmp, "icmpcreatefile");
picmpclosehandle = (pfnbh)getprocaddress(hicmp, "icmpclosehandle");
picmpsendecho = (pfndhdpwpippdd)getprocaddress(hicmp, "icmpsendecho");
if ((picmpcreatefile == 0) || (picmpclosehandle == 0) ||
(picmpsendecho == 0)) {
cerr << "failed to get proc addr for function." << endl;
return 4;
}
// 打开ping服务
handle hip = picmpcreatefile();
if (hip == invalid_handle_value) {
cerr << "unable to open ping service." << endl;
return 5;
}
// 构造ping数据包
char acpingbuffer[64];
memset(acpingbuffer, '\xaa', sizeof(acpingbuffer));
pip_echo_reply pipe = (pip_echo_reply)globalalloc( gmem_fixed | gmem_zeroinit,
sizeof(ip_echo_reply) + sizeof(acpingbuffer));
if (pipe == 0) {
cerr << "failed to allocate global ping packet buffer." << endl;
return 6;
}
pipe->data = acpingbuffer;
pipe->datasize = sizeof(acpingbuffer);
// 发送ping数据包
dword dwstatus = picmpsendecho(hip, *((dword*)phe->h_addr_list[0]),
acpingbuffer, sizeof(acpingbuffer), null, pipe,
sizeof(ip_echo_reply) + sizeof(acpingbuffer), 5000);
if (dwstatus != 0) {
cout << "addr: " <<
